RDF/XML is a syntax,[1] defined by the "W3C,[2] to express (i.e. "serialize) an "RDF graph as an "XML document. RDF/XML is sometimes misleadingly called simply RDF because it was introduced among the other W3C specifications defining RDF and it was historically the first W3C standard RDF serialization format. Although the RDF/XML format is still in use, other RDF serializations are now preferred by many RDF users, both because they are more human-friendly,[3] and because some RDF graphs are not representable in RDF/XML due to restrictions on the syntax of XML "QNames.